California ponders citrus quarantine after latest pest find

The discovery of an Asian citrus psyllid in the heart of California’s citrus producing area has the industry on edge awaiting a quarantine announcement.

“(The state) is being prudent in evaluating the best way to handle this,” said Bob Blakely, director of industry relations for California Citrus Mutual, Exeter.

As of Nov. 29, harvest continued unrestricted, said Gavin Iacono, Tulare County deputy agricultural commissioner, standards and quarantine.

“Right now, it’s the status quo until they actually decide what it is they’re going to do and how big the quarantine area is.”

Mandarins are currently being picked, and the Tulare County navel harvest is about 25% complete, Blakely said.

The California Department of Agriculture was reviewing the situation and was expected to announce quarantine boundaries and fruit movement requirements as early as the first week of December, said Steve Lyle, public affairs director.

The quarantine talk was triggered after the trapping of a citrus psyllid near a Strathmore citrus grove in October, marking the second psyllid find in a year. A trap 4 miles away caught one in February.

Meanwhile, a trap about 10 miles away, near a Terra Bella citrus grove, secured a psyllid in November.

Not only do psyllids feed on citrus trees, sucking the sap and weakening them, but they can carry citrus greening, a bacterial disease also called huanglongbing or HLB.

Although harmless to humans and animals, the citrus greening bacteria can stunt and even kill citrus trees.

The disease has caused more than $1.3 billion in losses to the Florida citrus industry, according to a University of Florida study.

It also has been found in Texas, Louisiana, Georgia and South Carolina.

Citrus greening was found in March in a residential tree in the Hacienda Heights area of Los Angeles County.

How much of an impact the quarantine will have on grower-packers and the ongoing citrus harvest in Tulare County will depend on the boundaries, Blakely said.

“It keeps changing,” Iacono said about possible boundaries. “Originally, it was the whole county, then a 20-mile radius. Now they’re talking about a couple of different scenarios.”

Tulare County Ag Commissioner Marilyn Kinoshita and her staff met with about 700 growers, packers, haulers and processors, Nov. 28, to discuss what they knew about the quarantine.

Under the proposal, growers within the quarantine zone could move fruit to packinghouses within the regulated area without additional restrictions, Iacono said.

Growers who wanted to move fruit out of the quarantine would first have to run it through a field-cleaning machine, which removes stems and leaves, or run it through brushes and rollers in a packinghouse within the quarantine, he said.

Field cleaning machines are rare in California’s Central Valley, and most were developed to handle fruit in Southern California and Arizona groves already under psyllid quarantines, he said.

Regardless of the method, the goal is to remove leaves and stems that might harbor hitchhiking psyllids before the fruit leaves the quarantine.

This requirement could pose hardships for growers used to selling mandarins into specialty markets that want leaves and stems attached, he said.

Blakely said he’s hopeful the Tulare County insects were just hitchhikers on illegal plant material from Southern California, where there’s an ongoing psyllid-control program and quarantine.

“What’s interesting about both of these finds is they were in traps that weren’t actually in trees but were on poles along a major highway where there’s a lot of fruit moving back and forth,” Blakely said. “There’s also fruit coming up from Southern California. It’s looking more like they were possibly brought into the area.”

Subsequent surveys and trapping of both groves by the ag commissioner’s office failed to find additional psyllids, he said.

Tulare County leads California in citrus production, with about 120,000 acres and a 2011 crop valued at more than $760 million, according to the ag commissioner’s annual crop report.